feat: Add DatabaseManager and LinkPlayer components, implement authentication and linking logic

- Created DatabaseManager component for managing database access via phpMyAdmin.
- Developed LinkPlayer component to link Discord accounts with game characters, including user authentication and error handling.
- Added mock data files for players, organizations, and projects to handle backend unavailability.
- Implemented AuthService for managing user authentication and session checks.
- Created DatabaseService to fetch and manage player, organization, and project data with fallback to mock data.
- Added HTML page for handling authentication unavailability.
- Developed a test script for validating Docker setup and required files.

docker-compose.yml

@@ -0,0 +1,77 @@
+services:
+  frontend:
+    build:
+      context: .
+      dockerfile: Dockerfile.frontend
+    labels:
+      - traefik.enable=true
+      - traefik.http.routers.vollidioten.rule=Host(`vollidioten.ceraticsoft.de`)
+      - traefik.http.routers.vollidioten.entrypoints=websecure
+      - traefik.http.routers.vollidioten.tls.certresolver=lets-encrypt
+      - traefik.http.services.vollidioten.loadbalancer.server.port=80
+    networks:
+      - external_web
+      - default
+    depends_on:
+      - backend
+    restart: always
+  backend:
+    build:
+      context: .
+      dockerfile: Dockerfile.backend
+    environment:
+      - DISCORD_CLIENT_ID=${DISCORD_CLIENT_ID}
+      - DISCORD_CLIENT_SECRET=${DISCORD_CLIENT_SECRET}
+      - SESSION_SECRET=${SESSION_SECRET}
+      - CALLBACK_URL=https://vollidioten.ceraticsoft.de/auth/discord/callback
+      - FRONTEND_URL=https://vollidioten.ceraticsoft.de
+      - DB_HOST=${DB_HOST:-db}
+      - DB_USER=${DB_USER:-obsidian_user}
+      - DB_PASS=${DB_PASS:-obsidian_pass}
+      - DB_NAME=${DB_NAME:-obsidian_db}
+    restart: always
+    networks:
+      - external_web
+      - default
+  #db:
+  #  image: mysql:8.0
+  #  command: --default-authentication-plugin=mysql_native_password
+  #  restart: always
+  #  environment:
+  #    MYSQL_DATABASE: obsidian_db
+  #    MYSQL_USER: obsidian_user
+  #    MYSQL_PASSWORD: obsidian_pass
+  #    MYSQL_ROOT_PASSWORD: root_secret_pass
+  #  volumes:
+  #    - db_data:/var/lib/mysql
+  #  networks:
+  #    - default
+  db:
+    image: mariadb:latest
+    restart: unless-stopped
+    environment:
+      MYSQL_ROOT_PASSWORD: fgterherthethehdfghfghdfghdfgh
+      MYSQL_DATABASE: obsidian_db
+      MYSQL_USER: obsidian_user
+      MYSQL_PASSWORD: obsidian_pass
+    volumes:
+      - ./database:/var/lib/mysql
+    networks:
+      - default
+  phpmyadmin:
+    image: phpmyadmin/phpmyadmin
+    restart: always
+    ports:
+      - 8081:80
+    environment:
+      PMA_HOST: db
+      MYSQL_ROOT_PASSWORD: root_secret_pass
+    depends_on:
+      - db
+    networks:
+      - default
+networks:
+  external_web:
+    external: true
+volumes:
+  db_data: null